Random Fibonacci Sequence - Growth Rate

Growth Rate

Johannes Kepler discovered that as n increases, the ratio of the successive terms of the Fibonacci sequence {Fn} approaches the golden ratio which is approximately 1.61803. In 1765, Leonhard Euler published an explicit formula, known today as the Binet formula,

It demonstrates that the Fibonacci numbers grow at an exponential rate equal to the golden ratio φ.

In 1960, Hillel Furstenberg and Harry Kesten showed that for a general class of random matrix products, the norm grows as λn, where n is the number of factors. Their results apply to a broad class of random sequence generating processes that includes the random Fibonacci sequence. As a consequence, the nth root of |fn| converges to a constant value almost surely, or with probability one:

An explicit expression for this constant was found by Divakar Viswanath in 1999. It uses Furstenberg's formula for the Lyapunov exponent of a random matrix product and integration over a certain fractal measure on the Stern–Brocot tree. Moreover, Viswanath computed the numerical value above using floating point arithmetics validated by an analysis of the rounding error.

Read more about this topic:  Random Fibonacci Sequence

Famous quotes containing the words growth and/or rate:

    Although its growth may seem to have been slow, it is to be remembered that it is not a shrub, or plant, to shoot up in the summer and wither in the frosts. The Red Cross is a part of us—it has come to stay—and like the sturdy oak, its spreading branches shall yet encompass and shelter the relief of the nation.
    Clara Barton (1821–1912)

    If you could choose your parents,... we would rather have a mother who felt a sense of guilt—at any rate who felt responsible, and felt that if things went wrong it was probably her fault—we’d rather have that than a mother who immediately turned to an outside thing to explain everything, and said it was due to the thunderstorm last night or some quite outside phenomenon and didn’t take responsibility for anything.
    D.W. Winnicott (20th century)